The Diatone 2019 GT R249+ is one of the newest series of micro quadctopers from Diatone that is built around the Mamba mini f4 stack.
The full range from smallest to largest includes:
As you can see there is a high degree of modularity - for all except the largest they share the same 1105 5500kV motors. All sizes feature a 3mm thich carbon baseplate except for the R239 which uses and injection moulded plastic chassis and prop-gaurds. All models share the same injection moulded lightweight canopy and mamba mini f4 stack.
I've chosen to review the R249+ since my experience with micro quadcopters has lead me to believe that this is the 'sweet' spot in terms of performance and staying small and discrete when flying.
Overall look and feel
The first thing I'll say is that this is a very polished looking quadcopter. The build is well put together and includes some thoughtful parts like buzzer, spare screws, cable ties etc. although sadly only one set of propellers are included. Most impressive is perhaps the canopy that ties everything together. This is not a 3d printed canopy (like on the Leader 2.5) but an injection moulded one meaning a tidier finish and lighter weight as well as providing much more torsional strength. The design is clever and ingregrates with the quad well and includes well though-out features like the camera protection moulded in. The canopy is common across all of their 2019 GT range and is available in clear, white or black. No doubt other colours will be available later too. A quick shout out that the kit also includes 2 battery straps - these are my new favourites - lightest I've come across at a hair over 2g and 150mm long.
A closer look at the specs (my comments in red)
Wheel base: 115mm A good tight frame for 2.5" props. carbon fibre thickness is 3.0mm
Propeller: 2.5 inch. These are gemfan 2540 props, simply the best 2.5" prop available
Color: lucency / black / white
Weight: 77g This is the weight without receiver or props. Weight with receiver, props, battery strap is just under 83g.
Lipo battery: support 4S (not included) Can support 4s but I feel more comfortable with 3s on 5500kV
Flight controller: Mamba F405 mini; MPU6000; AT7456 OSD; 16M flash; 5V 1A BEC. Very pleased for this to have F4 and blackbox flash for tuning. 1 spare UART available outside those used for receiver and vtx control
ESC: Mamba F25 / 25A 4S ESC Dshot600 2-4s capable. Pleasantly suprised that this has a current sensor - my first 20 x 20mm ESC to have one.
Motor: Mamba Racing MB1105 5500KV Good kV choice for 3s. These are made by BBB (3BR) - a well recognised motor manufacturer
Camera: RunCam Micro Swift. The original micro CCD cam and still very capable. A testament to reliability
VTX: RunCam TX200U 48CH 25 / 200mW - Piggback VTX that runs off 5v. Has OSD control. Needs unlocking - more below.
Setup prior to flying
Before anything else I'd recommend unlocking the video transmitter which is a Runcam TX200U. By default this is locked to 25mW transmission power and many of the channels cannot be accessed. By holding down the button for 10 seconds you can unlock the vtx meaning all available channels plus 200mW transmission power will be available via betaflight OSD (tramp protocol).
Next you'll need to add your own receiver and I use the XM+ (FRSKY) fairly exclusively. I don't use telemetry because the XM+ has a great feature that sends RSSI over an auxilliary channel so that it can be displayed in betaflight OSD (once firmware is updated). It's cheap too - Hobbycool.com have this permanently on sale at less than $10 here. Its very easy to wire up with the flight controller already pre-wired. The receiver can then easily be stuck to the top of the flight stack thanks to the plastic cover that is included.
Lastly I've captured the default betaflight settings below both in screenshot form and as a diff file but spoiler: This tune is awful, at least the version I have. Further down in the flight section I'll show updated screens and diff file.
First flight impressions?
Awful! After getting excited that there was a custom tune I was very disappointed to find out this tune was just rubbish. I switched to stock PIDs in betaflight OSD but this was even worse. I think someone has much about with the filters meaning it oscillates like crazy, even with extremely low (single digit!) P and D values on pitch and roll.
Resetting betaflight and next flight
Before taking to the sky again I updated to betaflight 3.5.3 but more importantly, reset all the custom settings. I then followed the betaflight 3.5 tuning guide here to enable all of my favourite settings like I-term relax and RC interpolation. Screenshots on the tune below and a diff file as well.
After tuning (using Albert Kim's betaflight tuning guide) I managed to get rid of the oscillations but still have some work to do in tightening it up. All of my tuning was done with a GNB 3s 450mah battery which I feel is a good match although anything up to about 650mah 3s would offer a little more flight time without compromising performance too much. Update: I now have my final tune in the gallery above. I'm pretty happy with it on 3s. It's conservative but not osciallation or Jello. Please make sure you run PID loop at no more the 4kHz.
The first thing I noticed about this quad it how quiet it is. I think this is because it is lighter than most and props aren't spinning as fast running 3s on a mid kV motor. Although not as quick as the Leader 2.5 (reviewed here) it was a lot more gentle on the battery meaning I could get a fairly comfortable 2.5-3 minutes from the 3s 450mah battery with low and fast flying which is reasonably intensive for a battery (vs. say floaty freestyle). That said I found throttle on this very linear with plenty of thrust up high in the throttle range where I'm used to it levelling off and just making more noise. Grip, cornering is all getting familiar now and assuming nothing strikingly wrong with the quad is more down to the software setting and tune than anything else. In terms of feel thought with was really good and given I have a preference for lower kV and lighter weight this suited my tastes well.
Although I prefer this quad with 3s it can most definitely handle 4s. I used my China Hobby Line Ministar 4s 650mah battery and dropped Ps and Ds a little to compensate. It is noticeably faster but I'm not a fan of this flying style where it is hard to scrub off momentum in a corner - it essentially becomes a flying bring (albeit a very fast flying brick). I'd still recommend 4s for wider open spaces if this is your only quad and yes it will perform well but I personally think wide open spaces are more suitable for larger quads. Again this is my bias showing through but I like this R249+ best on 3s and threading through smaller and more technical gaps. If you are looking for a 4s battery for this though I'd recommend a light 4s 450mah like this one from china hobby line. Update: PIDs finalised for 4s. I did quite a bit of work with D to make sure that motors were only slightly warm with a full, hard run on 4s 650mah.
Since I unlocked the VTX above, all of my flights have been on 200mW. Performance is good but not great. At first I was really impressed by the runcam VTX but after more high throttle runs I found out that there was noise coming through at high throttle. Given the runcam TX200u runs off the 5v supplied by the flight controller, the flight controllers' BEC may well be the culprit which is typical - this is what I found with the Leader 120 when I ran the vtx off the 5v line compared to battery voltage. Unfortunately though the TX200u only runs on 5v. Don't get me wrong though, it was fine, just not as clean as the Leader 2.5 or babyhawk R
Comparison to other 2.5" micros
The 2.5" brushless micro market is now relatively crowded so it's hard to stand out. I've been lucky enough to review a number of these so feel like I am in a good position to make these comparisons. There is enough differences between them in weight and motor spec to suggest some maybe more suitable than others (particularly if you have existing batteries you wish to use) but for a large part they are interchangeable.
So you can see by comparison this is relatively light for a modern 2.5" micro, only the Leader 120 is lighter. The components on the Leader 120 are now getting rather dated (although it can be greatly improved) so will take no further part in this comparison. The 1105 5500kV Motors for the 249+ are slightly smaller and lower kV than the other modern 2.5" quads and personally I find them more suitable for a light-ish 2.5 inch propeller. I also like the fact that I can get the bulk of the performance out of it on 3s unlike the skystars bolt that really needs a 4s, although it is nice that the option is available. Although the babyhawk r pro and leader 2.5 have electronics capable of managing 4s, their motors are too high in kV to be practical here.
For me the R249+ hits a nice balance on price, weight and power meaning it's not the fastest, lightest or most powerful but it is a good balance of these which makes for respectable battery life, good performance less noise during flight. In the end you'll probably be driven more on promotional prices than any specific features here and unless you are very passionate about something specific it would be hard to argue with that reasoning. I think the last word on this would be that the quality of Diatone, FullSpeed, and EMax are somewhat on par with the Skystars bolt somewhere behind. Same goes for availability of spare parts - Fullspeed, Diatone and Emax support their products well.
2019 GT R249+ Conclusion
Diatone have done a Diatone and released a very nice quad on paper but this time at a much more competitive price than the previous 2018 GTR90. The R249+ reviewed here shares the same electronics and motors as the 1.9 inch R239 and 2 inch R249 but the 1105 5500kV motors suit this size best rather than adding unneccessary weight with the smaller-propped versions. It's a very predictible flyer that is far from slow on 3s which I this is where the sweet spot is on this quad although you can run on 4s for more speed but also more weight.
Would I recommend it? Sure it's a good quad but no better or worse that the Leader 2.5 or Babyhawk R Pro. Diatone, Fullspeed and Emax all have a strong brushless micro pedigree and resultant support for these models so that is a wash too. Really it will come to price and that will change from time to time depending on promotions so at the prices listed above. For now, the Diatone GT R249+ and Leader 2.5 look to have the best offering and for me personally the Diatone edges the Fullspeed Leader 2.5 with a faster F4 processor and motors that better suit my flying style. See my leader 2.5 review here to compare. For me the Babyhawk R pro is just too expensive AND heavy.
The Diatone GT 90 (Rabbit) R249+ is available from Banggood here as a plug and fly model
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The Mobula7 is made by Happymodel who also released the popular Snapper7 which I reviewed here. Like the Snapper 7 it is a 75mm brushless whoop but it is lighter and more importantly, designed for 2s batteries. The Mobula 7 is not the first ready to fly 2s brushless whoop to the market but it is by far and away the lightest at just 28g without battery. That means the small and light 0802 16000kV motors are able to reach their power potential even on the small 260mah batteries included in the kit and make this quadcopter move very quickly with extremely nimble handling.
Specs and breakdown
As per the instructions you'll need to bind the receiver first. Since this receiver is integrated, binding process is really easy: power on THEN hold down for bind button for 2 seconds to enter bind mode. Don't need to hold down the tiny button when powering on!!! It's a small win but a win nonetheless. Please not the receiver bind button is underneath the canopy (you'll need to remove it). The button you can see underneath the quad is for the DFU FC boot mode.
Great news that at the time of writing the Mobula 7 ships with betaflight 3.5.0 which is the latest major release. It is fully setup out of the factory although you may want to set up your own rates, OSD and anything else that is unique to you. Please see below for all factory settings in screenshot form.
Batteries and throttle limit
The mobula7 is capable of both 1s and 2s power supply. The stock batteries are 1s but are designed to be used in series. If you are looking a new batteries I'd recommend 2s 250-350mah and changing the connector to a JST or XT30. Most people seem to be having success with the following hobbyking batteries:
Turnigy nano-tech 300mah 2S 45~90C Lipo Pack
Turnigy Nano-Tech Plus 300mAh 2S 70C Lipo Pack
If you are looking at flying indoors I'd recommend against using larger 1s batteries (450-600mah) but instead use a throttle limit in betaflight. The advantages here are lower current draw and less battery sag. Putting the limit in betaflight rather than on your radio gives you better control and allows you to put throttle limits on an auxilliary switch. Full details on how to limit throttle in betaflight 3.4.0 and up here.
There has been much already said about this quads performance and it is all true. You simply cannot compare this to any brushed whoop (e.g. santa whoop) or brushless whoop that has come before, 2s makes it so much more powerful and responsive. It flies like a full sized quadcopter in terms of ability to perform freestyle moves including dives, split s, power loops except that prop wash is exaggurated due to betaflights inability to cope with this well (compared to say, NFE silverware).
Where does the mobula 7 fit?
For me you cannot beat a lightweight 1s brushed whoop running NFE sliverware in tight indoor spaces for simplicity, agility and its ability not to get confused when you bump into things. In tight indoor spaces 2s on the Mobula 7 too sensitive on the throttle unless of course you limit throttle. For outdoor flight I prefer to have no prop gaurds on micros like on my eyas x2 build. So where does the mobula 7 fit in? I think the very best scenario is a large indoor area where you can really open it up or a smaller outdoor area where people or property can be upset - reason being it is tiny, quiet and if you do happen to crash into something or someone then between prop gaurds and the extremely light weight, that something or someone is unlikely to be damaged. Furthermore I often here people asking for 1 quad that can peform in all situations - not perfect for anything in particular but capable of all. I can think of not other quad that can perform this broad role better - for example 1s brushed quads lack power for outdoor flight and ductless brushed quads will damage an inside environment.
Below is a night time flight I did that should give you a feel of the camera performance in the dark which was surprisingly fly-able. As you can see I was fairly gentle on the throtte given the lighting.
It works! So much better than the 1s brushless quads - the extra voltage from 2s means turtle mode works just as well as the bigger quads on a hard surface.
Straight up this is not a strong frame, especially if you are flying in colder weather. It is however easy to fix with flexible e6000 glue available here but I would definitely recommend a spare frame available here for only $4. Apparently Happymodel are working on a new more durable frame. In my mind frame strength is the weakpoint on this quad.
I can genuinely see why there is a lot of hype around this quad. There is no other quad available at any price that will perform capable in both tight indoors and large outdoor space so competently. But this is not any price, it is just $80-$90 depending on where and when you buy it. Yes it has shortcomings, the frame is weak, ducts handle propwash poorly the camera performance and range is limited. But the fun this quad offers and represents easily offsets those issues. My final summary is this: If I were to go on a trip and take just 1 quad for ANY situation, it would be this one.
I hope you enjoyed the review, please feel free to like or share the article on facebook or anywhere else if you found it useful.
Spares available here:
The Leader 2.5 is a recent release from FullspeedRC and as well as being available on their own website, is also available from Banggood and Gearbest. If you do decide to purchase, Fullspeed over many more customisations and offer free shipping till Jan 2019. The Leader 2.5 follows the recent Leader 3 but is limited to 2.5 inch rather than 3 inch propellers. My objective for this blog is not to write a tradtional review due to the similarities to the Leader 3 but to cover the keys settings and physical changes I'd strongly recommend to enjoy this quadcopter.
The key differences to the Leader 3 (reviewed here) are as follows:
As you can see these differences are minimal, the key differences for flight performance will be the higher kV motors and of course the smaller propellers. It's an interesting choice that they went for an F3 rather than an F4 processor on the flight controller but for now this shouldn't make much difference especiallly if you use the F3 performance edition of Betaflight described here.
All betaflight settings as customised by fullspeedRC are shown below. I usually find this is an easier way to refer rather than looking through lines of code in the diff file (which I've also included below for completeness. As you can see this shipped with betaflight 3.3.0
A quick note on weight
Perhaps the key ingredient than made the original Leader 120 such a successful micro was it's light weight, coming in at less than 70g stock. Unfortunately the Leader 2.5 cannot keep this up largely due to the VASTLY improved camera, vtx and much larger motors. Weights with and without props are below for comparison.
Changes recommended before first flight
After the first 2 flights there are some immediate updates I'd recommend.
Next I'd recommend rotating the VTX by 180° so that the connector is at the back of the quad rather than the front, This will allow you to have better adjustment for camera angle. As you can see below I could not drop my camera angle to less than about 40° before I did this. UPDATE: I mentioned this to Lewis @ Fullspeed and they are now assembling this way.
Flight performance here is as expected and comparable with any modern 2.5" quadcopter. With 1106 7500kV motors it has a power edge over most though but you'll need good batteries to manage supply them. I'd recommend a 2s battery of around 650mah which should give you 3-4 minutes flight depending on how you fly. The GNB 3s 650mah would probably be the pick of the bunch and is available from Banggood or Gearbest amongst others.
Given I wanted to make a number of changes to betaflight settings I chose to update Betaflight to 3.5.1 performance edition (OMNIBUS target). So far I've had to dial back the P and D values around 10 points do reduce oscillations but will post PIDS here once I've refined a little more.
From testing around 50-60 packs I can say the frame is extremely strong with no signs of damage. It does a great job of protecting the camera and motors.
Below is DVR of some early flights:
In summary this quadcopter needs a few very minor tweaks out of the box for the best experience however once these are done (at very little cost) you have a very, very good 2.5" quadcopter with a strong featureset, particularly the powerful motors and VTX which allows up to 600mW transmit power and full tramp telemetry control via betaflight OSD.
Oddly the closest competition to this model is probably Full Speed's own Leader 3. Personally I do prefer the Leader 3 given the difference in retail price is only $4 and you get better props and a more capable FC out of the box. More relevant to this choice though is the motor kV and what batteries you have available. Outside of the Leader 3 though, the closest competition for the leader 2.5 is the Emax Babyhawk R Pro but at $170 retail price this is over $40 more expensive. The Leader 2.5 is a great step forward from the Leader 120 (reviewed and modded here) and brings the featureset up to date with common tech for 2018.
The Leader 2.5 is available from the following retailers that deliver worldwide:
If you haven't yet seen the first part of my Leader 3 (SE) review, click here. In it I cover an overview of the New Leader 3 including full discussion of the components, build and software setup. A quick correction too: I mentioned originally that the flight controller (namely the gyro) will only do 8kHz loop times. This is incorrect - it will actually run up to 32kHz! Certainly the first I'm aware of on a board this size and something for me to test in future.
Before I go any further I should note that my Leader 3 is a review model and so there may be minor improvements in the final version shipped to buyers. I'm in regular contact with Full Speed RC to give them feedback on what I find to assist with these improvements. The Leader 3 is available directly from FullSpeedRC.com, Gearbest or Bangood.
Since FPV performance is common between 3s and 4s I thought I'd cover that first. In short it is outstanding. Fullspeed RC shared a lot of the development of the included TX600 vtx with me an a lot of effort went in to ensuring a clean video signal all the way up to 600mW and the results sure doesn't disappoint. The result is that the Leader 3 has the cleanest video signal I have every used. There is absolutely no impact of throttle or other electrical noise on signal and it is hard to put in words just how much more enjoyable this makes the signal. I do miss the audio that AKK VTXs allow for but most people don't rate this as being important, especially on a micro. It's noteworthy that the the transmission power will go as high as 600mW - equalled only by the AKK FX3 ultimate (review here) in this form factor. OSD control of settings via Tramp works as expected. Antenna connection is via UFL is common for micros and fit for purpose.
No propellers in FPV view
Great news for those who don not like seeing their propellers - the frame design means that even with fairly modest camera angles of around 35°and up there are no props in view. Hopefully this is clear from my videos below. This also make the drums for a Caddx Turtles HD camera install beat even louder...
I wanted to clear things up on camera angle since Nick Burns mentioned it couldn't go past about 45° in his otherwise excellent review. I can confirm that the camera connector does not foul on the flight stack and does infact smoothly go all the way up to about 90° amgle. Pictures are best here so please see below:
Performance on 3s
When the Leader 3 was shipped to me, 2 custom PID prodiles were programmed in by fullspeed, Profile 1 was designed for 3s and profile 2 for 4s. 3s was tested with profile 2. Both of these profiles can be seen in full in part 1 of the review here. For 3s testing I used Turnigy Nanotech 3s 450mah 65c batteries. They weigh less than 45g meaning all up weight was around 140g. Flight time using these batteries was typically around 2.5-3 minutes with batteries coming to a resting voltage of arounf 3.75v per cell.
Flying exclusively with the HQ 3x3x3 propellers flight felt very 'balanced' - what I mean by that is the quad didn't feel overly heavy (or light), top speed was fast enough but not ludicrously fast like the Skystars Bolt X120 on 4s (review here). It was however very predictable - I could hit gaps and avoid obstacles in a way where I felt I had complete control. It was fairly similar to the way the Emax Babyhawk R 3 inch felt (review here) but the HQ props felt more predictable and familar compared to the EMAX Avans. This makes sense - both the Leader 3 and Babyhawk R are of similar weight and with 1106 4500kV motors on 3 inch props and both have optimised PID tunes. Full Speed RC seem to have done a good job on the tune here not just for the feel during flying but also in keeping propwash to a minimum, even when I tried to put myself in dirty air in 180° turns or descending directly down.
Below is a video from an early flight (2nd pack ever) in a local carpark. Typical I had DVR issues in a flight later that day where I'd gotten more familiar with the flight characteristics :/
Performance on 4s
The battery I used for all 4s testing was the China Hobbyline Ministar 4s 650mah pack. It is an excellent battery that I even use on my 4 inch racer so is very capable although a little heavy at 87g.
First of all I'm going to talk about straight up speed and my perception. It did not feel as fast as the Skystars Bolt X120 using the same battery. This is not an objective measure, purely feel. It did feel faster than the Babyhawk R 3" using the same battery.
To dig in to this further though I do need to say that that Skystars Bolt X120 is very hard to control with this battery and I did not enjoy flying it because it felt difficult to control. It felt like it needed more open space which then kinda defeats the purpose of a micro. By comparison the Leader 3 felt in complete control using 4s and PID profile 2 as customised for 4s by Full Speed RC. As a result it felt right at home on 4s with all the control and balance I felt on 3s. I think part of this is due to tune but moreso that that larger 3 inch blade is able to better support the additional weight from the heavier pack and hasn't overloaded the propeller (disc loading theory).
All other features of flight were similar to 3s - excellent video, precise handling and minimised propwash. I was really enjoying flying this until...
When I first received this model, Full Speed RC cautioned me to use 4s using the smaller Gemfan 2540 props (review here) since motors could overheat. Since I was the only reviewer to receive mine where it is winter presently rather than summer, this was less of an issue although I did keep an eye on motor temps. For this reason I stuck with the included 3 inch props for 4s.
About 10 packs in of warm motors (40-50°C only) I fell out of the sky when attempting a short speed run (see video below). On closer inspection the left rear corner had failed that I could later confirm as a motor failure (as opposed to ESC). The motor definitely was warm only as above and not hot. The only other time I've had a motor failure was on the babyhawk r when I used PIDs with too much P and D on 4s and even then the motor did not fail mid flight, rather afterwards intsead. This motor was scorching hot.
I discussed this with Full Speed RC and found that they will be using a stronger motor on the production version - the review version like I have are a prototype. As you can see below when comparing to my burnt out motor on the Emax Babyhawk R, the Fullspeed one does not look nearly as abused - it failed at a much lower load. Interestingly shortly after this I saw Andy RC's review and found he had an identical problem - motor failed mid run using 4s with HQ 3x3x3 props. Update: The prototype motors are actually 4800-4900kV and the production version will be 4500kV.
So, what does this mean for you? Until I can confirm that Fullspeed RC have moved away from the proptotype motors I can't recommend using the HQ 3x3x3 props with 4s, even in cold weather. For now stick with Gemfan 2540 props on 4s. Of course if it ships with new motors then all bets are off. Full Speed RC is sending me a full set of new motors so I will test with these and post my results in a follow up review as soon as I am able. Update: The prototype motors are actually 4800-4900kV and the production version will be 4500kV.
The Full Speed RC Leader 3 is as an excellent flyer on 3s - great video signal and predictable handling make for an enjoyable flying experience. On 4s the Jury is out... custom pids make this fly well too but the motors' inability to cope with the included 3" props are a bit disappointing. For now a bandaid solution is to run with Genfan 2540 props on 4s but I expect that Full Speed will release with a stronger motor for launch as they did with the original Leader 120. Again, my sample is a reviewer model and this feedback is used to make changes if needed to the final launch product. Full Speed RC has proven themselves to be a reputable company with well researched (and tested) quadcopters and I expect them to follow through on this model too.
This is part 2 of the review. In part 1 I discuss an overview and setup (including betaflight settings from factory) are covered in detail: Part 1 review
Firstly a very important correction. In the first review I showed a picture of the quadcopter minus battery sitting on a set of scales at 65g. I took this for granted and after measuring on my own scales got 84g. I don't usually trust weight in text but seeing it was sitting on digital scales I did not measure myself. Disappointing as this is misleading so I updated Gearbest immediately. To their credit they promptly took the image down and corrected the weight in the description - see below.
Preparing for flight
Just some minor housekeeping prior to the first flight. XM receiver was fixed in place on top of the VTX as it was dangling free when I received it. Antenna was fixed in place with a cable tie off the rear arm and heatshrink to secure. VTX antenna got the same treatment off the rear upper-deck of the frame. Lastly I replaced the rubbish battery strap with one from RJX hobbies (review here). Although a buckled strap was included as well as the one picture above, it was much too long? Weird.
Flight performance on 2s
Just because the Bolt X120 *can* fly on 2s doesn't mean you *should* fly on 2s. I used my Turnigy Nanotech 2s 950mah (47g) pack and needed about 40% throttle to hover. I could fly but performance was lacklustre and I got bored. I did get about 4 minutes flight time but won't say any more.
Flight performance on 3s
After my initial disappointment on the weight, performance on 3s 450mah turnigy nanotech was better than I had expected. It felt controlled with enough speed to be enjoyable. I had to switch to default betaflight 3.3 PIDs though since the customised PIDs look more like a 4s tune and felt sloppy as a result. I did manage to get good flight times on these little batteries of approximately 2.5 - 3.0 coming down at 3.75 volts and had fun doing so. Given then power of the quad I'd probably pefer a 650mah 3s for another minute or so of flight and would have less concern about sagging on big throttle punches. For the places I usually enjoy micros the most (tight with small trees) I found 3s the most fun.
Quick update: compared back to back on same batteries with my Leader 120 which is lighter (68g vs 84g) with 'smaller' motors (1104 7500kV vs. 1106 4500kV). I found it was similar speed with comparable handling and I actually got as good if not slightly better flight time on the Skystars Bolt - the extra stator size was negated by the lower kV from an efficiency standpoint. The leader however cannot do 4s...
When I went from 3s to 4s on the BabyHawk R 3" (review here) I got a reasonable increase in speed but not 33% as you'd probably expect. Given the same motor size (1106 4500kV) I was expecting something similar here but got a complete shock here - This thing ABSOLUTELY SCREAMS on 4s. I've always liked the Gemfan 2540 props (review here) but have never tried them on 4s and boy, they sure hold up and deliver on the extra power, it was like a different quad altogether. The speed was like nothing I'd felt on a micro and I had real trouble managing in a tight area. This probably wasn't helped by the fact I was using a CNHL Ministar 4s 650mah battery which weighs 87g so I was really blowing out on corners, even with a lot of extra throttle. It reminded my of running a heavy 4s 3 inch with 1408 motors - super fast but handled like a brick. I'd dare say 450mah 4s at around 62g would be a better option for weight control. at the cost of some flight time. As it stood I was getting 4 - 4.5 minutes on the 650mah battery. I've since moved to betaflight 3.4.0 and have got the tune tighter without oscillations but it is still a handful. For my piloting ability running this quad on 4s requires a bigger area akin to my 4 and 5 inch quads but that kind of deafeats the purpose of this micro. For my money and ability I actually prefer this on 3s - It is much quieter and handles better with the lower weight which is better suited to small parks. The noise alone on 4s makes people more wary of this one.
Rather than trying to recommend how many cells you should run I've merely stated my opinions on what I want from a micro. The most important thing here is that this Skystars Bolt X120 is well and truly capable of comfortably running 3s or 4s depending on where you are flying or how you are feeling on a particular day. The new throttle limiting feature on betaflight is a great way of limiting power to fly on 4s if for example you want to stick with just this battery size with power more akin to 3s. I've written a full tutorial on this here including how to assign to an AUX switch.
Although I alluded to the similarities to the original Leader 120 (review here) it is clearly a different quadcopter with a different feel and different capabilities - it has a much better camera and VTX but is much heavier and designed to run on more cells which make it heavier again for a different flight feel. A better comparison is perhaps the BabyHawk R 3 inch which I find handles better but lacks the speed of this model, particularly on 4s. Images below on a scale for all of these for comparison.
The Skystars bolt can be bought exclusively from Gearbest in several different formats - an unbuilt kit with no receiver (PNF), a built quad with no receiver, or as a built quad with FRSKY or Flysky receivers.
Check on my discounts page regularly for specials but at the time of writing the unbuilt kit is available for $117 and the FRSKY BNF as seen here is available for $134
So the Emax Hawk 5 has been out for a couple of months now and it has really captured the imagination of community. This is because it was an EMax-USA driven initiative that started as a way to sell more parts (Magnum stack, LS motors, Avan props) but ended up so much more. Where the Hawk 5 separates itself from all other bind and flys that have come before (except perhaps the holybro kopis) is that is more than the sum of it's parts - the development that has gone into matching the components, developing a strong, stiff yet lightweight frame and then tuning the whole package means it is a bind and fly that is genuinely competitive for racing out of the box. Listening to HyphPV and Sean Taylor in various channels they both believe this is a bonafide racer which is high praise coming from them.
I'll try keep this review brief because there has already been a lot said about this quad but I'll try to address the aspects that struck me as peculiar or aspects I don't thik have been well covered.
I think the component choice looks solid but unspectacular however the way that this comes together in for flight is super impressive.
Rather than going through the setup step by step in boring text, I've screen-grabbed all the relevant tabs from betaflight below. In short this quad includes custom filters setup, PIDs and rates so that you have an excellent tune right out of the box. This perfectly matches the specfic frame geometry, weight, motors and props that are used. Confident tuners will no doubt be able to adjust to their specific feel but I can say that I've come across no better custom tune in any quad yet, it is comparable to the babyhawk R (my review here) which makes sense - it was tuned by the same team.
Early flight performance
Wow. I had preconceptions that the 2206 low kV motors would be underpowered but was completely wrong. This is a fast, highly manouverable quad that is well tuned. To date it is the quickest quad I've flown and objectively has been found to hit over 100mph consistently. More than that though it corners well thanks to the 'grippy' props and light weight. I won't carry on here about flight but it felt well and truly locked in, the best quad I have flown.
In terms of FPV the signal was excellent on 25mW which is what I'm limited to on racing. There was absolutlely no sign of electrical interference or noise on my go-to channel (F2 - 5760MHz) at any throttle level. Just as importantly the image from the foxeer arrow micro pro is surprisingly good. This camera is a surprisingly good improvement over the micro arrow 1 or 2 and the micro swift 1 or 2 - I believe the presets were greatly approved on. I've actually ordered 3 more of these cameras to replace my others with because so far have not been a fan of the newer CMOS cameras.
One thing that felt unfamiliar to me were the way the props delivered power and the noise or the lack thereof. Additionally they pull a lot of current -I peaked at 110A on a 1500mah 4s pack. My guess is that in order to take advantage of the relatively low kV motor they went with a VERY agressive propeller with a distinct geometry. After swapping over to a HQ 5x4.8x3 which is stilla fairly agressive prop the Hawk 5 felt much more familiar and predicable to me with a power delivery and audible feedback I'm much more familiar with. I didn't feel I lost anything in speed or grip but peak current draw dropped off to 97A, i.e. 10% improved efficiency at high throttle. I need to note that props are a personal thing and this is my preference. You may find you like the stock Avan Flow props much more, I'm more of a HQ/Dal guy.
Lastly I'll say the efficiency on this is very impressive, again probably down to their choice of motor.. Everyone flies differently so will get different flight times depending on what they are doing but this I founf that even with my most tired 4s 1000mah pack I was able to get 3 minutes of flight which outperformed my lighter Floss 2 build which hand 'only' 2205 motors. On a good 1300mah I got 4 minute sof hard flying and from 1500mah about 4.5 - 5 minutes.
If you are looking for a 5" bind and fly quad quite simply this is the one to get. $250 sounds like a lot compared to other cheaper ones but as I've said before this is so much greater than the sum of it's parts. The clever choice of components, lightweight frame and wonderful tune make this a great quad and it shows - at the time of writing it is always in and out of stock depending on where you shop. Since so many have sold there is also a very big community - more people to solve problems and enhance. For example customs canopies, go pro mounts and recommendations for budget meaningful modifications and customisation is much more readliy available than for less common quads that tend to come and go. I'll bet this quad will be around and supported well for a long time.
Support is great - as you can see above all parts are available from many retailers so replacements are not just available but commonly available.
I can't speak to reliability yet since I haven't flown enough but since they haven't gone with the very latest and leading edge technology and hardware, that means there have been time to iron out the bugs. I'm expecting few problems but will certainly report back if there are.
Lastly I'll make a note again on the efficiency. In the race for power with bigger motors and steeper props this often gets forgotten but EMax seems to be going down the path of optimised efficiency and it shows here. The rhetoric from them is the the LS and newer RSII series are motor were not developed for all out power but more for efficiency which is what racers have really been demanding - making sure that on fast tracks that they still have battery left at the end. This is a benefit to the racer of course but for the casual pilot more efficiency = longer flight time = more stick time for learning and more of the the fun part of FPV... actual flying!
In summary this is a great model and comes highly recommended from me. Of course I'll be looking to improve where I can do so effectively and cheaply and will write about this where it's meaningful. Gearbest kindly supplied me this model and I'd encourage you to purchase from them as per the link below. Using this affiliate link comes at no cost to you but will help me to continue making and publishing reviews like this and recommendations for improvement.
Updates! I've new written a blog on bang for buck upgrades and also a comprehensive walkthrough on a VTX upgrade to allow DVR, smart audio, great power options.
The Beebee 66 is a micro 1s brushless powered quadcopter which is essentially a brushless Tiny Whoop. It is made by Full Speed RC, the same company that produced the highly successful Leader 120. (review here). Gearbest kindly supplied me a BNF Beebee 66 to review. I was desperately hoping for this to be the brushless answer to the tiny whoop but I'm really bummed out that it just isn't. Read on to find out why.
Adding a receiver
Since this was supplied as a BNF model, it came without a receiver. I opted to use the lightest FRSKY receiver I had on hand - an XM that I'd finally figured out how to fash with the RSSI channel 16 firmware. In most models this is a matter of soldering wires to the exposed pads on the top of the flight controller. However,since the FC and ESC are part of the structure of this quad AND the FC is flipped upside down to sit the ESC connector in a manageable location, the prop gaurd, 4 nylon nuts and the flight controller itself had to be removed before I could access the receiver solder pads. Then I needed the help of a multimeter to figure out ground, +5v and signal wires. Once soldered up with a short length of silicon wire to the receiver it was easy enough to re-assemble and tuck the XM reciever underneath the canopy behind the AIO camera/VTX. Pics below of course can explain this better:
It's not the end of the world wiring in a reciever here but can be fiddly with particularly small hardware. I'd recommend if you did buy this model that you purchase with the receiver of your choice pre-fitted.
Kept it pretty simple here. Because this is quite a different steup than I am used to I retained the stock settings on Betaflight 3.1.7 that it arrived with. All I did was set an arm switch and a mode switch for angle-horizon-air. Below are the default settings from Betaflight 3.1.7. Oh yeah, receiver had to be set up too. Like most f3 boards receiver is on UART 3.
The only other preparation was pretty straighforward. The included GNB High Voltage 1s 260mah Lipo battery was easily charged using the included USB adaptor and a micro usb cable I had on hand. Only 1 set of props was included that are press-fitted on the tiny 0705 fullspeed branded (Sunny Sky made) 0705 brushless motors. I left the VTX on the default channel for the initial flight that my Aomway Commanders (review here) picked up as 5905MHz.
Please look away if you love your Beebee 66 because it starts to get a bit ugly here. After fully charging the LiHV batteryand confirming everything was working ok I armed and found the props were fouling on the TPU canopy. Minor annoyance down to the tight tolerance in the slightly flexible TPU canopy. Easy enough to bend out of the way and I was back in action.
The first thing I noticed how loud the motors are - not in idle where they are practically silent but under any sort of load. Next as part of test with line of sight attempting a 'punchout' I could clearly see the quad dipping (pitch/roll) and twisting (yaw) under load. I'll attempt to tune this out later on and will post another review if successful. Moving on to line of sight I found the flight performance dull and uninspiring. What's worse was that after just one and a half minutes flight my battery was sagging down below 2.7v - the motors were clearly very demanding for their relatively mild output. I really wanted this quad to be a success and in fairness there is a chance I could have a less than perfect unit but my experience is my experience and I was disappointed. I do have some thoughts on how to improve though and I'll cover this in my Next Steps section below.
Comparison to a brushed micro
Please understand that these comments aren't made from isolation - I've had some experience with tiny whoops based on 7mm motors (like the JJRC H67 or Eachine E011) and although these are cheap brushed toy grade quads, they offered equivalent or better power and a flight time of 4 minutes plus on the same size battery with much smoother flight performance. A quick note that I actually tried the stock battery from the JJRC H67 (260mah non-HV) and got only 1 minute flight before it sagged below 2.7v under load. After recovery it bounced back to 3.65V but this same battery give my 4 minutes plus in my E011 FPV or santa whoop.
At this point I can't recommend this quad. The performance I experienced was poor and the flight time was unacceptable. My guess it that the brushless motors do not scale down well to 7mm, at this size the brushed motors seem to be more approprate. I'd recommend going in one of two directions:
I'm not content to leave things be with the Beebee 66 and the latest version of this model (Beebee 66 lite) has shown the direction I want to go in - removing weight. I'm skeptical of getting to the level of improvement I want but with some of the parts below I think I can replace the canopy with a simple camera holder. remove the propgaurd and TPU supports and save up to about 4g. Will this make enough difference? Not sure but will report back when I'm done. Make sure you bug me about the follow up in the comments if I'm too slow! Below are some of the weights of the components I'm interested in:
This is part 2 of my review of the Leader 120 by Full Speed from Gearbest. For part 1 click here. As at September 2017 try code HarvestRCnew7 to get this for only $US93.99!
None of the dreaded "brown outs" here
Straight up I have had none of the reported issues of brownouts as many of the youtube reviewers found on the first version of the Leader 120. In saying that my review modelis version 2 which I has the fullspeed branded black motors. The default idle speed of which there was a lot of chatter about was set at 10% from the factory in Betaflight 3.1.7. This is very high and reducing it to my regular 3.5% caused no issues. So on to the more interesting stuff!
This is a great little flier, As I expected from hearing the motors run in betaflight they are very quiet and coupled with the well-balanced KK 2840 props it lets off very little noise in flight. Coupled with the size, this makes it much more socially acceptable to be flying in areas that aren't completed isolated. The rates are not stock either and I actually really liked them, even compared to my stock betaflight 3.2.0 settings when I flew my 5" quad immediately afterwards. There are an awful lot of micros that have poor or no tuning from the factory so was escpecially pleased when the tuning here required practically nothing for those either lacking the know-how or too lazy to do. Power is excellent on 2s and comparable to many 2" quads on the 3s - the bigger props and relatively light weight really make these motors come alive. Handling was predicatable and I felt I had good control even in heavy gusts.
The stock battery can be described as adequate. I can see the voltage alarms were set low at 3.0 warning, 2.9 critical to allow for the sag but it keeps you in the air with moderate flying for up to 4 minutes. Considering I was able to flow without esc desync, losing vtx signal or getting failsafe, this probably makes it better than 90% of included batteries out there (not kidding).
I'll have a follow up tips and tricks article soon where I look at some of the other internationally available battery options including 3s.
FPV - Camera and VTX
Ahh a chink in the armour. Hitting a sharp price point eventually means compromise and I think I've found it. Typical of All In One (AIO) cameras this handled low light on a dull day poorly even with the focus correct. Kind of makes branches jump out at you when flying under trees - that's my excuse anyway. Secondly although the VTX does well enough for 25mW, it still only does 25mW. That means that I started seeing breakup at 100-150M away or as soon as I was on the wrong side of even small trees. The good news is you can pop this on your RC car or tiny whoop (I STRONGLY recommed the Eachine E011) and upgrade this one. There is more than enough lift for the extra weight of a micro CCD camera like the Foxeer arrow micro or Runcam swift micro and a Vtx like the new one from fullspeed that is 25mW/200mW switchable to mount on the back. I'll be making such a change in the near future and reporting back in a new article in the tips and tricks section.
This model is an amazing combination of well-matched parts with good assembly and a custom tune making it compelling on paper. I'm pleased to say that this transfers into flight characteristics and power making it an option you should definitely be considering if looking at a micro in 2017. I personally think this frame size that allows for a 2.8" prop rather than 2" is much better matched to this motor size and not nearly so sensitive to weight meaning for a more robust and enjoyable flying experience. My only real gripe is the video quality where camera light handling and vtx power lets it down. It is hard to argue at this price point though and in a future article I'll be doing a budget mod to address this.
Most interestingly, I built a model from parts that was very similar to this before this model was announced. Cutting to the chase the PNP version from Gearbest was more quiet and felt more solid in the air (perhaps due to the tune/rates) than my own build. Power was similar: although noisier I think the DYS motors had an edge although for the small difference I prefered the ones in this PNP model. I preferred the adjustible power vtx on the model I built to bump up power but this is really starting to split hairs. This does have me second guessing my build vs buy strategy but I think this is testament to the well thought out component list Full Speed have chosen.
Buy the Leader 120 from Gearbest